Need calculations for wall climbing RC car

[lorenzo55]

I am trying to imitate the Airhog zero gravity climber

one of these
http://www.gmhummer.com/forums/showthread.php?t=111

can someone please help me regarding derieving equations for the suction pressure required and regarding selection of motors for driving suction fans.
the toy basically uses an air venturi system so i am a bit unsure that the equations of a hovercraft would be applicable.
please help me out.

 

[lorenzo55]

can someone answer my query

 

[russ_watters]

Hmm.. I think that the volume of the suction cups will need to be calculated into the airflow requirement of the venturi. Other than that, you have pressure and area to find force and you'll need a coefficient of static friction to know if it'll slide down the wall.